Giant pituitary adenomas: an institutional experience with 289 surgically treated patients

Giant pituitary adenomas (GPA) are considered difficult to treat and the operative procedures are associated with more complications. This study aimed to assess treatment strategies of GPAs in a large consecutive and uniformly documented series in a single specialized center.

A total of 289 patients with GPA who underwent primary surgery in our department between December 1982 and December 2022 were analyzed in this retrospective study. GPAs were defined by a maximum diameter of ≥ 4 cm in at least one plane. Patients were reviewed for endocrine, radiological and ophthalmological outcomes as well as complication and mortality rates.

The mean maximum tumor diameter was 4.6 ± 0.7 cm. 201 patients (69.6%) underwent transsphenoidal and 36 patients (12.4%) underwent transcranial surgery only. 52 patients (18.0%) underwent a combined approach within a few weeks. Gross-total resection (GTR) was achieved in one-fifth (n = 52) of the patients. It was dependent, among other factors, on patients' tumor size and tumor extension. Severe complications such as tumor apoplexy, meningitis or cerebrospinal fluid leaks occurred in 5.9%, 3.5% and 2.8% of patients, respectively. Seven deaths (2.4%) occurred in the early postoperative period. The median follow-up time was 76 months, at which point 70.2% of patients showed a stable condition without requiring further treatment.

Generally, the treatment of giant pituitary adenomas remains a significant challenge. Although the transsphenoidal approach achieved good results, tumor size and configuration often required a transcranial approach or a combination of different approaches. It is important to consider individual patient and tumor characteristics when selecting the most appropriate surgical approach.